U.S. patent number 10,139,815 [Application Number 15/107,363] was granted by the patent office on 2018-11-27 for chiller control device, chiller, and chiller diagnostic method.
This patent grant is currently assigned to MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD.. The grantee listed for this patent is MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD.. Invention is credited to Yoshie Kanki, Minoru Matsuo, Takaaki Miura, Kenji Ueda.
United States Patent |
10,139,815 |
Miura , et al. |
November 27, 2018 |
Chiller control device, chiller, and chiller diagnostic method
Abstract
This chiller control device (74) is provided with: a storage
unit (18) which stores operation data detected at each site in a
turbo chiller; a compression unit (34) which, when the size of the
operation data accumulated over time in the storage unit (18)
becomes too large, converts the operation data each time a
condition depending on the type of operation data is met, thereby
compressing the data size; and a diagnostic unit (36) which
evaluates the state of the turbo chiller on the basis of the
operation data converted by the compression unit (34). By this
means, the state of the chiller can be diagnosed without increasing
the storage capacity of the storage medium that stores operation
data of the turbo chiller.
Inventors: |
Miura; Takaaki (Tokyo,
JP), Ueda; Kenji (Tokyo, JP), Kanki;
Yoshie (Tokyo, JP), Matsuo; Minoru (Tokyo,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD. |
Tokyo |
N/A |
JP |
|
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Assignee: |
MITSUBISHI HEAVY INDUSTRIES THERMAL
SYSTEMS, LTD. (Tokyo, JP)
|
Family
ID: |
54008975 |
Appl.
No.: |
15/107,363 |
Filed: |
February 24, 2015 |
PCT
Filed: |
February 24, 2015 |
PCT No.: |
PCT/JP2015/055127 |
371(c)(1),(2),(4) Date: |
June 22, 2016 |
PCT
Pub. No.: |
WO2015/129657 |
PCT
Pub. Date: |
September 03, 2015 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170003679 A1 |
Jan 5, 2017 |
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Foreign Application Priority Data
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|
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Feb 28, 2014 [JP] |
|
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2014-039908 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B
41/043 (20130101); F25B 49/022 (20130101); G05B
23/0221 (20130101); F25B 1/10 (20130101); F25B
40/02 (20130101); F25B 25/005 (20130101); F25B
49/005 (20130101); F25B 2700/21172 (20130101); F25B
2700/21171 (20130101); F25B 2600/2501 (20130101); F25B
2700/193 (20130101); F25B 1/053 (20130101); F25B
2339/047 (20130101); F25B 2700/195 (20130101); F25B
2400/23 (20130101); F25B 2700/21173 (20130101); G05B
2219/2613 (20130101); F25B 2341/0662 (20130101); F25B
2600/0261 (20130101); F25B 2700/21161 (20130101); F25B
2700/197 (20130101); F25B 2700/21163 (20130101); F25B
31/023 (20130101); F25B 2400/13 (20130101) |
Current International
Class: |
G05B
23/02 (20060101); F25B 1/10 (20060101); F25B
49/02 (20060101); F25B 41/04 (20060101); F25B
40/02 (20060101); F25B 25/00 (20060101); F25B
1/053 (20060101); F25B 31/02 (20060101); F25B
49/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1499636 |
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May 2004 |
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CN |
|
102345950 |
|
Feb 2012 |
|
CN |
|
102384855 |
|
Mar 2012 |
|
CN |
|
102707713 |
|
Oct 2012 |
|
CN |
|
2003-15734 |
|
Jan 2003 |
|
JP |
|
2005-49945 |
|
Feb 2005 |
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JP |
|
2011-3038 |
|
Jan 2011 |
|
JP |
|
2012-52733 |
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Mar 2012 |
|
JP |
|
2013-36632 |
|
Feb 2013 |
|
JP |
|
Other References
Chinese Office Action dated Jun. 23, 2017 in corresponding Chinese
Application No. 201580003437.3 with an English Translation. cited
by applicant.
|
Primary Examiner: Tran; Vincent H
Attorney, Agent or Firm: Birch, Stewart, Kolasch &
Birch, LLP
Claims
The invention claimed is:
1. A chiller control device included in a chiller, the chiller
control device comprising: storage means for storing operation data
which is detected at each site in a chiller; compression means for
converting, when the size of the operation data accumulated in the
storage means over time increases, the operation data each time a
condition corresponding to the type of the operation data is met,
and compressing the data size; and state evaluation means for
evaluating the state of the chiller on the basis of the operation
data which is converted by the compression means.
2. The chiller control device according to claim 1, wherein the
compression means compresses the data size by smoothing the
operation data for every division corresponding to a size of an
operation parameter of the chiller, and wherein the state
evaluation means calculates a difference between the operation data
compressed by the compression means and a reference value
corresponding to the division, and evaluates the operation state of
the chiller by comparing the difference and a threshold value
corresponding to the division.
3. The chiller control device according to claim 2, wherein the
state evaluation means informs a different evaluation result
according to a deviation state between the difference and the
threshold value.
4. A chiller comprising: a turbo compressor to compress a coolant;
a condenser to condense said compressed coolant into a condensed
coolant; a sub cooler that supercools said condensed coolant; one
or more expansion valves to expand the liquid coolant; an
evaporator to evaporate the expanded liquid coolant; and a chiller
control device comprising: storage means for storing operation data
which is detected at each site in a chiller; compression means for
converting, when the size of the operation data accumulated in the
storage means over time increases, the operation data each time a
condition corresponding to the type of the operation data is met,
and compressing the data size; and state evaluation means for
evaluating the state of the chiller on the basis of the operation
data which is converted by the compression means.
5. The chiller according to claim 4, wherein the compression means
compresses the data size by smoothing the operation data for every
division corresponding to a size of an operation parameter of the
chiller, and wherein the state evaluation means calculates a
difference between the operation data compressed by the compression
means and a reference value corresponding to the division, and
evaluates the operation state of the chiller by comparing the
difference and a threshold value corresponding to the division.
6. The chiller according to claim 5, wherein the state evaluation
means informs a different evaluation result according to a
deviation state between the difference and the threshold value.
7. A chiller diagnostic method for a chiller using a chiller
control device included in the chiller, the method comprising: a
first step of storing operation data, which is detected at each
site in a chiller, in storage means; a second step of converting,
when the size of the operation data accumulated in the storage
means over time increases, the operation data each time a condition
corresponding to the type of the operation data is met, and
compressing the data size; and a third step of evaluating the state
of the chiller on the basis of the compressed operation data.
Description
TECHNICAL FIELD
The present invention relates to a chiller control device, a
chiller, and a chiller diagnostic method.
BACKGROUND ART
A control device of a chiller such as a turbo chiller is configured
such that only data required for controlling a device is input and
stored. Accordingly, a storage capacity of a storage medium for
storing data is small.
In order to diagnose an operation state, a failure prediction, or
the like of a chiller, detailed operation data such as temperature
data or pressure data of the device constituting the chiller is
required, and various operation data should be accumulated (stored)
in time series. Accordingly, more accurate diagnosis is possible as
an amount of accumulation of the operation data increases.
Therefore, it is necessary to increase the storage capacity of the
storage medium for storing the operation data.
Accordingly, as described in PTL 1, in order to diagnose the
operation state, the failure prediction, or the like of the
chiller, the diagnosis is performed by a device including a storage
medium having a larger storage capacity such as a control board or
a remote monitoring device which is provided outside the
chiller.
CITATION LIST
Patent Literature
[PTL 1] Japanese Unexamined Patent Application Publication No.
2012-52733
SUMMARY OF INVENTION
Technical Problem
However, in a case where diagnosis of a chiller is performed by a
control panel, a remote monitoring device, or the like, it is
necessary to collect operation data from the chiller via a
communication line. However, a communication data amount which is
transmittable and receivable via the communication line is limited,
and the diagnosis may be performed by only the limited operation
data. In addition, there is a chiller in which the remote
monitoring device is not introduced, and in this chiller, the
diagnosis itself may be not performed.
Therefore, preferably, diagnosis using more operation data is
performed by a control device capable of collecting the operation
data without using the communication line. However, as described
above, the storage capacity of the storage medium included in the
control device is small, and if the storage capacity increases, a
cost increases.
The present invention is made in consideration of the
above-described circumstances, and an object thereof is to provide
a chiller control device, a chiller, and a chiller diagnostic
method capable of diagnosing the state of the chiller without
increasing a storage capacity of the storage medium which stores
the operation data of the chiller.
Solution to Problem
In order to achieve the object, a chiller control device, a
chiller, and a chiller diagnostic method of the present invention
adopt the following means.
According to a first aspect of the present invention, there is
provided a chiller control device, including: storage means for
storing operation data which is detected at each site in a chiller;
compression means for converting, when the size of the operation
data accumulated in the storage means over time increases, the
operation data each time a condition corresponding to the type of
the operation data is met, and compressing the data size; and state
evaluation means for evaluating the state of the chiller on the
basis of the operation data which is converted by the compression
means.
According to this configuration, the operation data which is
detected at each site of the chiller is stored in the storage
means. For example, each site of the chiller is a relay, an
inverter, a compressor, a heat exchanger, or the like. For example,
the operation data is the number of times of opening and closing of
the relay, a temperature of the inverter, an electric motor current
and an evaporator pressure of the compressor, a cooling water
outlet temperature, a condensation-saturation temperature, and a
cooling water flow rate of the heat exchanger, or the like.
If the operation data is accumulated in the storage means over
time, the data size increases. In order to continuously store the
operation data having the increased data size, the storage capacity
of the storage means should be increased.
Accordingly, with respect to the operation data having the
increased data size, the operation data is converted by the
compression means each time the condition corresponding to the type
of the operation data is met, and the data size is compressed.
Accordingly, since the data size of the operation data decreases,
it is not necessary to increase the storage capacity of the storage
means. For example, the condition corresponding to the type of the
operation data is a continuous operation time of the chiller, or
the like. In addition, the conversion is extracting an evaluable
and necessary portion in the state of the chiller by smoothing the
operation data using averaging, approximating, or the like.
In addition, the state of the chiller is evaluated by the state
evaluation means on the basis of the operation data converted by
the compression means.
Therefore, according to this configuration, it is possible to
diagnose the state of the chiller without increasing the storage
capacity of the storage medium which stores the operation data of
the chiller. Moreover, according to this configuration, since the
state of the chiller can be diagnosed by the chiller control
device, unlike the related art, a customer who does not have a
remote monitoring device or the like having a diagnosis function
can perform the diagnosis of the chiller. In addition, since the
operation data which is detected at each site of the chiller is
compressed and stored, a long-term diagnosis at each site of the
chiller can be performed by the chiller control device.
In the first aspect, preferably, the compression means compresses
the data size by smoothing the operation data for every division
corresponding to a size of an operation parameter of the chiller,
and the state evaluation means calculates a difference between the
operation data compressed by the compression means and a reference
value corresponding to the division, and evaluates the operation
state of the chiller by comparing the difference and a threshold
value corresponding to the division.
According to this configuration, the operation data for every
division corresponding to the size of the operation parameter of
the chiller is classified. For example, the operation parameter of
the chiller is an output load or a vane opening, and the division
is an output load ratio or an angle of the vane opening.
The operation data is smoothened by the compression means for every
division corresponding to the size of the operation parameter of
the chiller. In addition, the difference between the compressed
operation data and the reference value corresponding to the
division is calculated, the difference and the threshold value
corresponding to the division are compared with each other, and the
operation state of the chiller is evaluated.
Therefore, according to this configuration, it is possible to
evaluate the state of the chiller by simple processing without
increasing the storage capacity of the chiller control device.
In the first aspect, preferably, the state evaluation means informs
a different evaluation result according to a deviation state
between the difference and the threshold value.
According to this configuration, a manager of the chiller can
correctly determine the state of the chiller.
According to a second aspect of the present invention, there is
provided a chiller including the above-described chiller control
device.
According to a third aspect of the present invention, there is
provided a chiller diagnostic method, including: a first step of
storing operation data, which is detected at each site in a
chiller, in storage means; a second step of converting, when the
size of the operation data accumulated in the storage means over
time increases, the operation data each time a condition
corresponding to the type of the operation data is met, and
compressing the data size; and a third step of evaluating the state
of the chiller on the basis of the compressed operation data.
Advantageous Effects of Invention
The present invention provides a remarkable effect which can
diagnoses the state of the chiller without increasing the storage
capacity of the storage medium which stores the operation data of
the chiller.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a diagram showing a schematic configuration of a turbo
chiller according to an embodiment of the present invention.
FIG. 2 is a functional block diagram showing a configuration of a
chiller control device according to the embodiment of the present
invention.
FIG. 3 is a functional block diagram showing configurations of a
calculation processing unit and a storage unit according to the
embodiment of the present invention.
FIG. 4 is a flowchart showing a flow of data compression and
diagnosis processing according to the embodiment of the present
invention.
DESCRIPTION OF EMBODIMENTS
Hereinafter, an embodiment of a chiller control device, a chiller,
and a chiller diagnostic method according to the present invention
will be described with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of a turbo
chiller 11.
The turbo chiller 11 applies cold heat to chilled water which is
supplied to an external load 86 such as an air conditioner or a fan
coil. The turbo chiller 11 includes a turbo compressor 60 which
compresses a coolant, a condenser 62 which condenses a
high-temperature and high-pressure gas coolant compressed by the
turbo compressor 60, a sub cooler 63 which supercools a liquid
coolant condensed by the condenser 62, a high pressure expansion
valve 64 which expands the liquid coolant from the sub cooler 63,
an intermediate cooler 67 which is connected to the high pressure
expansion valve 64 and is connected to an intermediate step of the
turbo compressor and a low pressure expansion valve 65, and an
evaporator 66 which evaporates the liquid coolant expanded by the
low pressure expansion valve 65.
The turbo compressor 60 is a two-stage centrifugal compressor, and
is a fixed speed machine which is driven at a constant rotation
number. In addition, the fixed speed machine is exemplified in FIG.
1. However, a turbo compressor in which the rotation number is
variably controlled by an inverter may be used. An inlet guide vane
(hereinafter, referred to as an "IGV") 76 which controls a flow
rate of the suction coolant is provided in the coolant suction port
of the turbo compressor 60, and a capacity of the turbo chiller 11
can be controlled.
A condensed coolant pressure sensor PC for measuring a condensed
coolant pressure is provided in the condenser 62. The sub cooler 63
is provided on the downstream side of the coolant flow of the
condenser 62, and is provided so as to supercool the condensed
coolant. A temperature sensor Ts which measures the temperature of
the supercooled coolant is provided immediately after the
downstream side of the coolant flow of the sub cooler 63.
A cooling water pipe 80 for cooling the condenser 62 and the sub
cooler 63 is provided in the condenser 62 and the sub cooler 63.
The cooling water pipe 80 is connected to a cooling tower 83, and a
cooling water circulates through portions among the condenser 62,
the cooling tower 83, and the sub cooler 63 via the cooling water
pipe 80. The circulating cooling water absorbs a condensation heat
(exhaust heat) from the coolant in the condenser 62, radiates the
absorbed heat in the cooling tower 83, and is returned to the sub
cooler 63. The heat radiated in the cooling tower 83 undergoes heat
exchange with the outside air. In this way, the exhaust heat
discharged when the coolant is condensed by the condenser 62 is
removed by the cooling tower 83. The cooling water flowing through
the cooling water pipe 80 is pressurized and fed by a cooling water
pump 84 which is installed in the cooling water pipe 80. The
cooling water pump 84 is driven by an inverter motor for cooling
water pump (not shown). Accordingly, it is possible to variably
control a discharge flow rate of the cooling water pump 84 by
changing the rotation number of the inverter motor.
A cooling water inlet temperature is measured by a temperature
sensor Tcin which is installed in the vicinity of the inlet of the
sub cooler 63 of the cooling water pipe 80, a cooling water outlet
temperature is measured by a temperature sensor Tcout which is
provided in the vicinity of the outlet of the condenser 62 of the
cooling water pipe 80, and the cooling water flow rate is measured
by a flow meter F2 which is installed in the cooling water pipe
80.
A pressure sensor PM for measuring an intermediate pressure is
provided in the intermediate cooler 67.
A pressure sensor PE for measuring an evaporation pressure is
provided in the evaporator 66. Chilled water having a rated
temperature (for example, 7.degree. C.) is obtained by sucking heat
in the evaporator 66. That is, the heat of the chilled water
flowing in a chilled water pipe 82 inserted into the evaporator 66
is deprived by the coolant, and the chilled water is cooled. The
chilled water flowing through the chilled water pipe 82 is
pressurized and fed by a chilled water pump 85 which is stalled in
the chilled water pipe 82. The chilled water pump 85 is driven by
an inverter motor for chilled water pump (not shown). Accordingly,
it is possible to variably control a discharge flow rate of the
chilled water pump 85 by changing the rotation number of the
inverter motor.
A chilled water inlet temperature is measured by a temperature
sensor Tin which is installed in the vicinity of the inlet of the
evaporator 66 of the chilled water pipe 82, a chilled water outlet
temperature is measured by a temperature sensor Tout which is
provided in the vicinity of the outlet of the evaporator 66 of the
chilled water pipe 82, and the cooling water flow rate is measured
by a flow meter F1 which is installed in the cooling water pipe
82.
A hot gas bypass pipe 79 is provided between a gas phase portion of
the condenser 62 and a gas phase portion of the evaporator 66. In
addition, a hot gas bypass valve 78 for controlling the flow rate
of the coolant flowing in the hot gas bypass pipe 79 is provided.
By adjusting a hot gas bypass flow rate using the hot gas bypass
valve 78, it is possible to perform a capacity control in a
significantly small region in which the control is not sufficient
performed in the IGV 76.
FIG. 1, measurement values measured by various sensors such as the
pressure sensor PC are sent to a chiller control device 74. In
addition, the chiller control device 74 controls openings of the
IGV 76 and the hot gas bypass valve 78.
In the turbo chiller 11 shown in FIG. 1, the case is described in
which the condenser 62 and the sub cooler 63 are provided, heat
exchange is performed between the cooling water in which heat is
discharged to the outside in the cooling tower 83 and the coolant,
and the cooling water is heated. However, for example, instead of
the condenser 62 and the sub cooler 63, an air heat exchanger may
be installed, and heat exchange may be performed between the
outside air in the air heat exchanger and the coolant. In addition,
the present invention is not limited to the case where the turbo
chiller 11 has only the above-described cooling function. For
example, the turbo chiller 11 may have only a heating function, or
may have both the cooling function and a heating function.
Moreover, a medium which undergoes heat exchange with the coolant
may be water or air.
Next, a state evaluation of the turbo chiller 11 which is performed
in the chiller control device 74 included in the above-described
turbo chiller 11 will be described with reference to the
drawings.
For example, the chiller control device 74 includes a Center
Processing Unit (CPU), a Random Access Memory (RAM), a Read Only
Memory (ROM), a computer readable nonvolatile storage medium, or
the like. In addition, as an example, a series of processing for
realizing various functions is stored in a storage medium or the
like in a program type, the CPU reads the program on the RAM or the
like, and various functions are realized by performing processing
and calculation processing of information. In addition, as the
program, a program which is installed in the ROM or other storage
mediums in advance, a program which is supplied in a state of being
stored in a computer readable storage medium, or a program which is
transmitted via communication means such as wireless communication
or wired communication may be applied. The computer readable
storage medium is a magnetic disk, an magneto-optical disk, a
CD-ROM, a DVD-ROM, a semiconductor memory, or the like.
FIG. 2 is a functional diagram showing the configuration of the
chiller control device 74.
The chiller control device 74 performs chiller diagnosis processing
which evaluates the state of the turbo chiller 11 on the basis of
the operation data detected at each site of the turbo chiller
11.
For example, the site of the turbo chiller 11 is a relay, an
inverter, the turbo compressor 60, the heat exchangers (evaporator
66, condenser 62, and sub cooler 63), or the like. In addition, in
descriptions below, the site of the turbo chiller 11 is referred to
as a control object 10.
For example, the operation data is the number of times of opening
and closing of the relay, a temperature of the inverter, an
electric motor current and an evaporator pressure of the turbo
compressor 60, a cooling water outlet temperature, a
condensation-saturation temperature, and a cooling water flow rate
of the heat exchanger, or the like, and the operation data is
detected by the above-described various sensors.
The chiller control device 74 includes an input/output unit 12, an
input/output processing unit 14, a calculation processing unit 16,
a storage unit 18, and a communication unit 20.
The input/output unit 12 is connected to various sensors, and the
above-described operation data (analogue signals) is input to the
input/output unit 12 from various sensors. Moreover, the
input/output unit 12 may output detection start signals or
detection stop signals from various sensors. In addition, the
input/output unit 12 performs analogue/digital conversion on the
operation data which is the analogue signal so as to convert the
operation data into digital signals, and outputs the digital
signals to the input/output processing unit 14.
The input/output processing unit 14 outputs the operation data
input via the input/output unit 12 to the calculation processing
unit 16 or the storage unit 18, or outputs the signals from the
calculation processing unit 16 to the input/output unit 12.
In order to control the turbo chiller 11, the calculation
processing unit 16 generates control signals with respect to
various control objects, or performs chiller diagnosis processing
on the basis of the operation data.
The storage unit 18 is a nonvolatile storage medium which stores
various data such as the operation data. In addition, various
operation data (hereinafter, referred to as "reference operation
data") when a trial operation of the turbo chiller 11 is performed
is stored in the storage unit 18. The reference operation data is
the operation data which is obtained in a case where the trial
operation of the turbo chiller 11 is performed at a rated load or a
partial load, and is used in the chiller diagnosis processing.
In addition, an accumulated time (hereinafter, referred to as an
"elapsed time") while the turbo chiller is operated, various
correction coefficients used in the chiller diagnosis processing, a
threshold value, or the like is stored in the storage unit 18.
The communication unit 20 is connected to a display device 22 or a
remote monitoring device 24 via a communication line, and informs
the operation state of the turbo chiller 11 or the result of the
chiller diagnosis processing. Moreover, the communication line is a
line through which the digital signals are transmitted. The display
device 22 displays various processing signals by the chiller
control device 74. The remote monitoring device 24 can remotely
operate the turbo chiller 11.
FIG. 3 is a functional block diagram showing the configurations of
the calculation processing unit 16 and the storage unit 18.
The storage unit 18 includes a temporary storage memory space 30
and a compression data memory space 32.
The temporary storage memory space 30 sequentially stores the
operation data which is output from the input/output processing
unit 14. The compression data memory space 32 stores operation data
(hereinafter, referred to as "compression operation data") which is
subjected to the operation data compression processing by the
calculation processing unit 16.
The calculation processing unit 16 includes a compression unit 34
and a diagnostic unit 36.
The compression unit 34 stores the operation data stored in the
temporary storage memory space 30 in the compression data memory
space 32 as the compression operation data which is subjected to
the operation data compression processing.
The diagnostic unit 36 performs the chiller diagnosis processing on
the basis of the compression operation data.
Here, the operation data compression processing will be described
in detail.
The operation data output from the input/output processing unit 14
is sequentially stored in the temporary storage memory space 30.
Accordingly, the operation data is accumulated in the temporary
storage memory space 30 over time, and a data size increases.
In order to continuously store the operation data having the
increased data size, a storage capacity of the storage unit 18
should be increased, and a cost of the chiller control device 74
increases.
Accordingly, the operation data having the increased data size is
converted by the operation data compression processing each time a
condition (hereinafter, referred to as a "compression timing
condition") corresponding to the type of the operation data is met,
and the data size is compressed. The compression operation data is
stored in the compression data memory space 32, and the operation
data used in the compression is deleted from the temporary storage
memory space 30. Accordingly, since the data size of the
compression operation decreases, it is not necessary to increase
the storage capacity of the storage unit 18.
In addition, for example, the condition corresponding to the
operation data is a continuous operation time of the turbo chiller
11 or the like. In addition, the conversion is extracting an
evaluable and necessary portion in the state of the turbo chiller
11 by smoothing the operation data using averaging, approximating,
or the like.
In addition, since the temporary storage memory space 30
temporarily stores the operation data, the temporary storage memory
space 30 may not be a fixed memory space. However, preferably, the
compression data memory space 32 is a fixed memory space.
Next, a specific example of the operation data compression
processing will be described.
For example, in a case where the operation data is the number of
times of opening and closing of the relay, "1" is incremented to
the temporary storage memory space every one opening and closing of
the relay. In addition, if the number of times of opening and
closing of the relay which are sequentially stored in the temporary
storage memory space 30 exceeds 1000 times, the compression unit 34
determines that the compression timing condition is met. In
addition, "1000" which is the operation data stored in the
temporary storage memory space 30 by the operation data compression
processing is converted into "1", and "1" is stored in the
compression data memory space 32 as the compression operation
data.
In addition, in a case where the compression operation data
indicating the number of times of opening and closing of the relay
is already stored in the compression data memory space 32, the
compression operation data indicating the number of times of
opening and closing of the relay is incremented by "1". That is,
for example, if the number of times of opening and closing of the
relay is 100,000 times, the compression operation data indicating
the number of times of opening and closing of the relay stored in
the compression data memory space 32 becomes "100".
Moreover, for example, in a case where the operation data has a
temporal change such as the electric motor current and the
evaporator pressure of the turbo compressor 60, and the cooling
water outlet temperature, the condensation-saturation temperature,
and the cooling water flow rate of the heat exchanger, the
operation data is stored in the temporary storage memory space 30
in time series. In addition, if a predetermined time (for example,
one minute) elapses after the previous operation data compression
processing is performed, the compression unit 34 determines that
the compression timing condition is met. In addition, the operation
data which is stored in the temporary storage memory space 30 by
the operation data compression processing is averaged and
converted, and is stored in the compression data memory space 32 as
the compression operation data. Accordingly, the compression
operation data which is averaged every one minute is sequentially
stored in the compression data memory space 32.
In addition, the compression unit 34 may perform the average
stepwise such that the compression unit 34 averages the compression
operation data, which is averaged every one minute, every one hour,
averages the compression data, which is averaged every one hour,
every one day, and averages the compression data, which is averaged
every one day, every one month.
In addition, the compression unit 34 may smoothen the operation
data for every division corresponding to the size of an operation
parameter of the turbo chiller 11 so as to compress the data size.
For example, the operation parameter of the turbo chiller 11 is an
output load or an opening of the IGV (hereinafter, referred to as a
"vane opening"), and the division is an output load ratio or an
angle of the vane opening. The output load ratio is a value when
the rated load of the turbo chiller 11 is set to 100%.
FIG. 4 is a flowchart showing the flow of the data compression and
diagnosis processing including the operation data compression
processing and the chiller diagnosis processing. The data
compression and diagnosis processing is performed by the chiller
control device 74, starts if the turbo chiller 11 is operated, and
ends if the turbo chiller 11 stops. In addition, in the chiller
diagnosis processing, a compression timing or a diagnosis timing
described below is determined and performed every various operation
data.
First, in Step 100, the operation data which is input via the
input/output unit 12 is stored in the temporary storage memory
space 30 included in the storage unit 18.
Next, in Step 102, it is determined whether or not the compressing
timing condition of the operation data is met, and in a case of
positive determination, the step proceeds to Step 104. Meanwhile,
in a case of negative determination, the step returns to Step 100,
and the operation data is continuously stored in the temporary
storage memory space 30.
In Step 104, the operation data compression processing is
performed.
Next, in Step 106, it is determined whether or not the timing
reaches a timing in which the chiller diagnosis processing is
performed, in a case of positive determination, the step proceeds
to Step 108, and in a case of negative determination, the step
returns to Step 100.
In Step 108, the chiller diagnosis processing is performed on the
basis of the compression operation data.
Next, in Step 110, it is determined whether or not it is necessary
to inform the result of the chiller diagnosis processing, in a case
of positive determination, the step proceeds to Step 112, and in a
case of negative determination, the step returns to Step S100.
In Step 112, the result of the chiller diagnosis processing is
informed to the display device 22 or the remote monitoring device
24, and the step returns to Step 100.
Next, a specific example of the data compression and diagnosis
processing will be described.
First, a case where the object of the data compression and
diagnosis processing is the heat exchanger will be described. Since
the number of tubes may be several hundred in the heat exchanger
and corrosion of the heat exchanger significantly influences the
turbo chiller 11, correction determination of a deterioration state
is required.
The operation data required for the diagnosis with respect to the
heat exchanger is the cooling water outlet temperature, the
condensation-saturation temperature, the cooling water flow rate,
the output load of the chiller, or the like. The cooling water
outlet temperature and the condensation-saturation temperature are
associated with the cooling water flow rate and the output load
ratio of the chiller.
In addition, the operation data is divided according to a load as
an operation parameter of the turbo chiller 11. Specifically, the
output load ratio is divided into eight such as 20%, 30%, . . .
90%, and 100% (rated), the operation data in which the output load
ratio is equal to or more than 15% and less than 25% is divided so
as to be approximated as the operation data in which the output
load ratio is 20%, and the operation data in which the output load
ratio is equal to or more than 25% and less than 35% is divided so
as to be approximated as the operation data in which the output
load ratio is 30%. Similarly, the operation data in which the
output load ratio is equal to or more than 85% and less than 95% is
divided so as to be approximated as the operation data in which the
output load ratio is 90%, and the operation data in which the
output load ratio is equal to or more than 95% and less than or
equal to 100% is divided so as to be approximated as the operation
data in which the output load ratio is 100%.
In addition, in the operation data compression processing, each of
the cooling water outlet temperature and the
condensation-saturation temperature divided according to the output
load ratio is averaged every predetermined time (for example, one
hour) so as to compress the data size.
Next, the chiller diagnosis processing is performed on the basis of
the compression operation data.
A result, which is obtained by multiplying a temperature difference
(hereinafter, referred to as a "detection temperature difference")
between the cooling water outlet temperature and the
condensation-saturation temperature which are the compression
operation data by a predetermined correction coefficient, is
corrected by the current cooling water flow rate or the output load
ratio of the turbo chiller 11, and the diagnosis value is
calculated.
Meanwhile, a diagnosis reference value is calculated by multiplying
a temperature difference (hereinafter, referred to as a "reference
temperature difference") between the cooling water outlet
temperature and the condensation-saturation temperature which are
obtained from the reference operation data according to the
division corresponding to the diagnosis value, by a correction
coefficient corresponding to the operation elapse time of the turbo
chiller 11.
In addition, in the chiller diagnosis processing, a difference
(hereinafter, referred to as a "diagnosis temperature difference")
between the diagnosis value and the diagnosis reference value is
calculated, and the operation state of the turbo chiller 11 is
evaluated by comparing the diagnosis temperature difference and the
threshold value corresponding to the division. In addition, the
threshold value may be changed according to the operation elapse
time of the turbo chiller 11. For example, the threshold value is
set so as to be small as the elapse time is longer, and the
deterioration state of the turbo chiller 11 is strictly
determined.
Next, in the chiller diagnosis processing, the different evaluation
result according to a deviation state between the diagnosis
temperature difference and the threshold value is informed.
Accordingly, a manager of the turbo chiller 11 can correctly
determine the state of the turbo chiller 11.
In a case where the diagnosis temperature difference does not
exceed the threshold value X, it is determined that the diagnosis
temperature difference and the threshold value are not deviated
from each other and the heat exchanger does not deteriorate, and no
notification is performed. Alternatively, it is informed that the
state is not in the deterioration state. Meanwhile, if the
diagnosis temperature difference exceeds the threshold value X, it
is determined that the state is a deviation state and the heat
exchanger deteriorates, and an alarm is informed.
For example, in a case where the diagnosis temperature difference
exceeds the threshold value X and a first time or more elapses in
the duration time, in the chiller diagnosis processing, an alarm in
which the state is in a first-degree deterioration state is
informed. For example, in the case where the state is in the
first-degree deterioration state, a predetermined location on the
screen of the display device 22 is displayed by yellow.
In addition, in a case where the diagnosis temperature difference
exceeds the threshold value X+a predetermined value Y and a second
time or more elapses in the duration time, in the chiller diagnosis
processing, an alarm in which the state is in a second-degree
deterioration state is informed. For example, in the case where the
state is in the second-degree deterioration state, a predetermined
location on the screen of the display device 22 is displayed by
orange.
Moreover, in a case where the diagnosis temperature difference
exceeds the threshold value X+a predetermined value Y+a
predetermined value Z, in the chiller diagnosis processing, an
alarm in which the state is in a third-degree deterioration state
is informed. For example, in the case where the state is in the
third-degree deterioration state, a predetermined location on the
screen of the display device 22 is displayed by red. In addition,
in the case where it is determined that the state is in the
third-degree deterioration state, the chiller control device 74 may
stop the turbo chiller 11.
Next, a case where the object of the data compression and the
diagnosis processing is the turbo compressor 60 will be described.
The turbo compressor 60 is a main portion of the turbo chiller 11.
Accordingly, if the turbo compressor 60 fails, the turbo compressor
60 is removed and required to be repaired in a factory, and since
the turbo compressor 60 largely influences the turbo chiller 11,
the correct determination of the deterioration state is
required.
The operation data for diagnosing the turbo compressor 60 is the
electric motor current, the vane opening, the output load ratio of
the chiller, or the like. In addition, the electric motor current
is associated with the vane opening or the output load ratio.
In addition, the electric motor current is divided into eight
according to the output load ratio of the turbo chiller 11, in the
operation data compression processing, the electric motor currents
divided according to the output load ratio are averaged every
predetermined time (for example, one day) so as to compress the
data size.
In addition, in a case where the vane opening is excessively
changed, the value of the electric motor current is not used in the
operation data compression processing. If the vane opening is
excessively changed, the electric motor current may be changed.
Accordingly, this operation data is used, accuracy of the diagnosis
decreases.
Next, the chiller diagnosis processing is performed on the basis of
the compression operation data.
In the chiller diagnosis processing, a difference (hereinafter,
referred to as a "diagnosis current difference") between the
compression operation data which is the electric motor current and
the electric motor current obtained from the reference operation
data according to the division is calculated, and the operation
state of the turbo chiller 11 is evaluated by comparing the
diagnosis current difference and the threshold value corresponding
to the division.
Moreover, typically, after the turbo chiller 11 is shipped from a
factory and several years elapse, deterioration of the turbo
compressor 60 occurs. Accordingly, for example, an alarm is
informed in two stages. For example, in a case where integration of
cases where the diagnosis current difference exceeds the threshold
value is less than 20 times, in the chiller diagnosis processing,
when the diagnosis current difference exceeds the threshold value,
a low level alarm is informed, and when the integration exceeds 20
times, an intermediate level alarm is informed.
In addition, for example, in the chiller diagnosis processing, "1"
is incremented as the number of times of abnormal variation each
time the compression operation data indicating the electric motor
current or the evaporator pressure is changed to be equal to or
more than a predetermined value within a short time (for example,
one minute), in a case where the number of times of abnormal
variation is maintained during a predetermined time or more or in a
case where the number of times of abnormal variation which
repeatedly occurs is equal to or more than a predetermined number
of times, an alarm may be informed.
In addition, the chiller diagnosis processing may be performed on
the basis of a lubricant system of the turbo compressor 60. The
operation data required in this case is a condenser pressure, a
lubricant pressure, the evaporator pressure, or the like.
In addition, the operation data is divided according to the vane
opening which is the operation parameter of the turbo chiller 11.
Specifically, the vane opening is divided into nine such as 10%,
20%, . . . 90%, and 100%), the operation data in which the vane
opening is equal to or more than 5% and less than 15% is divided as
the operation data in which the vane opening is 10%, and the
operation data in which the vane opening is equal to or more than
15% and less than 25% is divided as the operation data in which the
vane opening is 20%. Similarly, the operation data in which the
vane opening is equal to or more than 85% and less than 95% is
divided as the operation data in which the vane opening is 90%, and
the operation data in which the vane opening is equal to or more
than 95% and less than or equal to 100% is divided as the operation
data in which the vane opening is 100%.
In addition, in the operation data compression processing, each of
the lubricant pressure and the evaporator pressure corresponding to
the divided vane opening is averaged every predetermined time (for
example, one hour) so as to compress the data size.
Next, the chiller diagnosis processing is performed in the basis of
the compression operation data.
By multiplying a pressure difference (hereinafter, referred to as a
"detection pressure difference") between the lubricant pressure and
the evaporator pressure which are the compression operation data by
a predetermine correction coefficient on the basis of the
relationship between the condenser pressure and the evaporator
pressure, the diagnosis value is calculated.
In addition, in the chiller diagnosis processing, a difference
(hereinafter, referred to as a "diagnosis pressure difference")
between the diagnosis value and the diagnosis reference value
according to the type of the turbo chiller 11 is calculated, and
the operation state of the turbo chiller 11 is evaluated by
comparing the diagnosis temperature difference and the threshold
value corresponding to the division. In addition, the threshold
value may be changed according to an operation time of an oil pump.
For example, the threshold value is set so as to be small as the
operation time is longer, and the deterioration state of the oil
pump is strictly determined.
Next, in the chiller diagnosis processing, the different evaluation
result according to a deviation state between the diagnosis
pressure difference and the threshold value is informed.
In a case where the diagnosis pressure difference does not exceed
the threshold value X, it is determined that the diagnosis
temperature difference and the threshold value are not deviated
from each other and the turbo chiller 11 does not deteriorate, and
no notification is performed. Alternatively, it is informed that
the state is not in the deterioration state. Meanwhile, if the
diagnosis pressure difference exceeds the threshold value X, it is
determined that the state is a deviation state and the turbo
chiller 11 deteriorates, and an alarm is informed.
For example, in a case where the diagnosis pressure difference
exceeds the threshold value X and a first time or more elapses in
the duration time, in the chiller diagnosis processing, an alarm in
which the state is in a first-degree deterioration state is
informed. For example, in the case where the state is in the
first-degree deterioration state, a predetermined location on the
screen of the display device 22 is displayed by yellow.
In addition, in a case where the diagnosis pressure difference
exceeds the threshold value X+the predetermined value Y and a
second time or more elapses in the duration time, in the chiller
diagnosis processing, an alarm in which the state is in a
second-degree deterioration state is informed. For example, in the
case where the state is in the second-degree deterioration state, a
predetermined location on the screen of the display device 22 is
displayed by orange.
Moreover, in a case where the diagnosis pressure difference exceeds
the threshold value X+the predetermined value Y+the predetermined
value Z, in the chiller diagnosis processing, an alarm in which the
state is in a third-degree deterioration state is informed. For
example, in the case where the state is in the third-degree
deterioration state, a predetermined location on the screen of the
display device 22 is displayed by red. In addition, in the case
where it is determined that the state is in the third-degree
deterioration state, the chiller control device 74 may stop the
turbo chiller 11.
In addition, in a case where the object of the data comparison and
diagnosis processing is the relay, in the data compression and
diagnosis processing, a value when the number of times of opening
and closing of the relay stored as the compression operation data
exceeds 200 times is set to the threshold value, and an alarm is
informed.
Moreover, in a case where the object of the data comparison and
diagnosis processing is a capacitor of the inverter, in the data
compression and diagnosis processing, the temperature of the
inverter stored as the compression operation data is multiplied by
a correction coefficient corresponding to the operation time of the
turbo chiller 11, and in a case where the multiplication value
exceeds the threshold, an alarm is informed.
In addition, since the chiller control device 74 stores the
operation data which is detected at each site of the turbo chiller
11, the chiller control device 74 can display maintenance
information at each site of the turbo chiller 11 with respect to
the display device 22.
In addition, for example, in the basis of the result (a
deterioration state at each site of the turbo chiller 11) of the
chiller diagnosis processing, the chiller control device 74 may set
a maintenance timing early with respect to a site in which
deterioration proceeds, and the chiller control device 74 may set a
maintenance timing late with respect to a site in which
deterioration does not proceed.
In this way, since the chiller control device 74 compresses and
stores the operation data, various operation data is stored for a
long period. Accordingly, the display device 22 can use the
operation data in the determination of the maintenance timing.
As described above, the chiller control device 74 according to the
present embodiment, includes the storage unit 18 which stores the
operation data which is detected at each site in the turbo chiller
11, the compression unit 34 which converts, when the size of the
operation data accumulated in the storage unit 18 over time
increases, the operation data each time the condition corresponding
to the type of the operation data is met, and compresses the data
size, and the diagnostic unit 36 which evaluates the state of the
turbo chiller 11 on the basis of the operation data which is
converted by the compression unit 34.
Accordingly, the chiller control device 74 can diagnose the state
of the turbo chiller 11 without increasing the storage capacity of
the storage medium which stores the operation data of the turbo
chiller 11.
Therefore, since the state of the turbo chiller 11 can be diagnosed
by the chiller control device 74, unlike the related art, a
customer who does not have a remote monitoring device or the like
having a diagnosis function can perform the diagnosis of the turbo
chiller 11.
In addition, since the operation data which is detected at each
site of the turbo chiller 11 is compressed and stored, a long-term
diagnosis at each site of the turbo chiller 11 can be performed by
the chiller control device 74.
Hereinbefore, the present invention is described using the
embodiment. However, the technical scope of the present invention
is not limited to the range described in the embodiment. Various
modifications and improvements can be applied to the embodiment
within the scope which does not depart from the gist of the
invention, and aspects to which the modifications and the
improvements are applied are also included in the technical scope
of the present invention. In addition, the embodiments may be
appropriately combined.
Moreover, the flow of the data compression and diagnosis processing
described in the embodiment is an example. Accordingly, within the
scope which does not depart from the gist of the present invention,
an unnecessary step may be removed, a new step may be added, or the
processing order may be changed.
REFERENCE SIGNS LIST
10: control object 11: turbo chiller 18: storage unit 34:
compression unit 36: diagnostic unit 74: chiller control device
* * * * *